1. Field of the Invention
The present invention relates to a miticide.
2. Description of Prior Art
Fruit trees, industrial crops, vegetbles and ornamental plants, such as citrus fruit, apple, pear, tea, cotton, Japanese cedar trees, eggplant, cucumber, strawberry, rose, carnation, chrysanthemum, etc., in the past have been known to be damaged by mites. Control of mites has been difficult. The lifetime of each generation of mites is usually about 20 days. One generation of mites will produce as many as 10 or more generations each year. In order to control each generation, therefore, it becomes necessary to apply the miticides repeatedly. The difficulty with repeated applications, however, is that due to the rapid regeneration of the mites, the mites tend to develop a resistance to the repeatedly applied miticides, which build-up of resistance seems to be developed more rapidly than the build-up of resistance of many other insects to insecticides.
The development period of mites involves successive growth stages starting from the ovum, extending to larva, and finally reaching the formation of adults capable of reproduction.
Thus, it would be most desirable to provide a miticide which will act simultaneously as adulticides, larvicides, ovicides, and which additionally maintain their effect over a long period of time.
In the present invention, S-.beta.-naphthylmethyl-N,N-dimethylthiolcarbamate has been found to possess miticidal characteristics which are quite different from conventional miticides. This compound, however, is not novel per se. Japanese Pat. Publication No. 4525/1973 discloses that this compound has been used as a herbicide, but it has not heretofore been disclosed as possessing any miticidal characteristics.